ieee802154: add netlink APIs for smartMAC configuration

Introduce new netlink attributes for SET_PHY_ATTRS:
 * CSMA minimal backoff exponent
 * CSMA maximal backoff exponent
 * CSMA retry limit
 * frame retransmission limit

The CSMA attributes shall correspond to minBE, maxBE and maxCSMABackoffs of
802.15.4, respectively. The frame retransmission shall correspond to
maxFrameRetries of 802.15.4, unless given as -1: then the old behaviour
of the stack shall apply. For RF2xy, the old behaviour is to not do
channel sensing at all and simply send *right now*, which is not
intended behaviour for most applications and actually prohibited for
some channel/page combinations.

For all values except frame retransmission limit, the defaults of
802.15.4 apply. Frame retransmission limits are set to -1 to indicate
backward-compatible behaviour.

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/nl_policy.c b/net/ieee802154/nl_policy.c
index 55b5616..fd7be5e 100644
--- a/net/ieee802154/nl_policy.c
+++ b/net/ieee802154/nl_policy.c
@@ -57,5 +57,10 @@
 	[IEEE802154_ATTR_LBT_ENABLED] = { .type = NLA_U8, },
 	[IEEE802154_ATTR_CCA_MODE] = { .type = NLA_U8, },
 	[IEEE802154_ATTR_CCA_ED_LEVEL] = { .type = NLA_S32, },
+	[IEEE802154_ATTR_CSMA_RETRIES] = { .type = NLA_U8, },
+	[IEEE802154_ATTR_CSMA_MIN_BE] = { .type = NLA_U8, },
+	[IEEE802154_ATTR_CSMA_MAX_BE] = { .type = NLA_U8, },
+
+	[IEEE802154_ATTR_FRAME_RETRIES] = { .type = NLA_S8, },
 };